This application is a reapplication from the University of Texas Southwestern Medical Center (UTSW) to participate in the multi-center clinical program, the Eunice Kennedy Shriver NICHD Cooperative Multicenter Neonatal Research Network (NRN). UTSW has been a member of the NRN since its inception in 1986. Pablo S nchez, MD, Luc Brion, MD, and Roy Heyne, MD remain as the Principal Investigator (PI), Alternate PI, and Follow-up PI, respectively. As an NRN clinical center, UTSW has the necessary academic, research and clinical infrastructure already in place that will assure continued excellence in the performance of NRN studies. The UTSW Neonatal-Perinatal division has demonstrated a strong commitment to clinical research, and in this endeavor, it has the strong support of the UTSW Pediatric Department as well as of its clinical facilities. Parkland Memorial Hospital (PMH) and Children's Medical Center (CMC) where the clinical studies pertaining to this RFA will be conducted. PMH boasts the largest inborn delivery service in the United States, while the CMC NICU is a new, state-of-the art facility. The Obstetric Dept. of UTSW and PMH is part of the Maternal Fetal Medicine Unit, assuring a continued source of diverse patients for clinical studies. This patient population is predominantly Hispanic, an underserved but increasing population whose inclusion in clinical trials is essential in order to reduce the health disparities that plague this ethnic group. UTSW has a proven track record within the NRN, as evidenced by its well organized clinical research system with a high percent- age of eligible infants enrolled in randomized trials, excellence in conducting the studies, and complete data acquisition. Follow-up of study infants is integrated within the infant's medical home at CMC, and the follow- up rates are among the highest in the NRN. The PI has extensive experience in the performance of multi- center, randomized clinical trials, such as the one proposed for the concept application consisting of prolonged administration of vitamin A and inhaled nitric oxide for prevention of bronchopulmonary dysplasia. By being board certified in both Neonatology and Pediatric Infectious Diseases, Dr. S nchez will provide expertise to the NRN on issues in neonatal infectious diseases, a vexing problem among low birth weight infants.